This invention relates to antibiotic derivatives of apramycin and intermediates in the synthesis therefor. In particular, it relates to apramycin derivatives in which the 4"-amino group is derivatized by a C.sub.2 to C.sub.4 -alkyl, C.sub.1 to C.sub.4 -acyl, benzyl, methoxybenzyl, halobenzyl, .gamma.-amino-.alpha.-hydroxybutyryl, .beta.-amino-.alpha.-hydroxypropionyl, glycyl, 4-amino-2-hydroxybutyl, 3-amino-2-hydroxypropyl or 2-aminoethyl group; and the pharmaceutically acceptable acid addition salts thereof.
Apramycin is used as a veterinary antibiotic (see U.S. Pat. Nos. 3,961,279, 3,853,709 and 3,876,767) and has the following structure: ##STR1##
It is known in the art that substitution on various positions of the aminoglycoside rings may increase the activity of the parent aminoglycoside. Some recent substituted-apramycin derivatives, in which the 1, 3 and 2'-amino groups were derivatized, have been reported by Herbert A. Kirst, Brenda A. Truedell and John E. Toth in Tetrahedron Letters, vol. 22, pp 295-298 (1981).
The apramycin derivatives of the instant application are substituted at the 4"-position and possess broad-spectrum antibiotic activity while differing in structure from the aforementioned compounds and other compounds previously disclosed in the art.